This invention relates generally to mechanisms for loading containers onto trucks, and, more specifically, to truck-mounted lifting mechanisms for loading containers onto the trucks for safe transport over intermediate and long hauls.
In the waste disposal industry, a standard disposal bin can hold three to four cubic yards of refuse. Many disposal accessability, such as garages of apartment and condominium complexes, and thus must be moved to other more convenient locations for emptying. Smaller trucks having a rear-mounted tilting forklift mechanism, which only lifts and tilts the container, have been employed in moving these disposal bins. However, due to the size of these trucks and the manner in which they carry containers beyond the rearward edge of the truck bed, they have been considered generally unsuitable for transporting containers over intermediate and long distances. Moreover, the usefulness of these smaller trucks has been further diminished by the increasing use of enlarged waste bins having capacities of eight cubic yards or more. These enlarged bins, when filled with refuse, can often weigh more than the lifting capability of the trucks.
Several manufacturers have begun installing lifting mechanisms on the rear ends of one and two-ton trucks in order to accommodate the new enlarged containers. These one and two-ton trucks are usually maneuverable enough to have access to most remote container storage locations, and yet heavy enough to handle the enlarged containers for at least short hauls. Typically, these larger trucks have employed lifting and tilting mechanisms very similar to those used previously on the smaller trucks. However, since these new larger trucks still generally lift and carry the enlarged containers beyond the rearward edge of the truck bed, several serious and potentially dangerous problems have arisen.
When a container is carried beyond the rear end of a truck bed, the weight of the container is primarily borne by the rear wheels. If the container is full of material, such as refuse, this rearward positioning can create a levered effect on the truck, with the rear wheels supplying the fulcrum. Such a condition can cause the front wheels to bounce off the ground when the truck is moving, resulting in an unsafe driving condition. Moreover, the unbalanced loading of the truck chassis accelerates wear and tear on the truck itself.
Accordingly, there has been a need for an economical and reliable, truck-mounted bin lifting mechanism which can lift and load enlarged containers so that they are positioned over the truck bed for safe transport over intermediate and long hauls. It is preferable that the improved lifting mechanism be capable of positioning the container so that its weight is reasonably distributed between the front and rear wheels. Also, the improved bin lifting mechanism should be able to hold the container securely in place over the truck bed to prevent its unintentional movement with respect to the truck during travel. Moreover, it would be desirable to provide readily accessible controls for the mechanism, both somewhere near the truck bed as well as within the truck cab, to maximize operator control over the lifting and loading of the container or bin. The present invention fulfills these needs and provides other related advantages.